Alert archive / Texas / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 240

June 6, 202128 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Jun 6, 2021, 9:42 PM CDT for 28 counties in Texas. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jun 6, 2021, 9:42 PM CDT (02:42 UTC)
Expired
Jun 7, 2021, 4:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 28 counties

Armstrong County, TX, Briscoe County, TX, Carson County, TX, Castro County, TX, Childress County, TX, Collingsworth County, TX, Cottle County, TX, Crosby County, TX, Dickens County, TX, Donley County, TX, Floyd County, TX, Garza County, TX, Gray County, TX, Hale County, TX, Hall County, TX, Hockley County, TX, Kent County, TX, King County, TX, Lamb County, TX, Lubbock County, TX, Lynn County, TX, Motley County, TX, Potter County, TX, Randall County, TX, Stonewall County, TX, Swisher County, TX, Terry County, TX, Wheeler County, TX

The radar

The Amarillo radar (KAMA), 100 km from the middle of the area, began a volume at 02:44 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
10%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

11 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jun 6, 10:14 PM CDTSevere Thunderstorm WarningAMARandall30 min
Jun 6, 10:18 PM CDTSevere Thunderstorm WarningLUBCastro, Swisher42 min
Jun 6, 10:21 PM CDTSevere Thunderstorm WarningLUBCastro, Hale, Lamb, Swisher39 min
Jun 6, 10:59 PM CDTSevere Thunderstorm WarningLUBCastro, Hale, Lamb, Swisher61 min
Jun 6, 11:19 PM CDTSevere Thunderstorm WarningLUBLynn, Terry56 min
Jun 6, 11:45 PM CDTSevere Thunderstorm WarningLUBBriscoe, Floyd, Hale, Swisher60 min
Jun 7, 12:15 AM CDTSevere Thunderstorm WarningLUBGarza, Lynn60 min
Jun 7, 12:43 AM CDTSevere Thunderstorm WarningLUBBriscoe, Crosby, Dickens, Floyd, Hale, Hall and 1 more48 min
Jun 7, 1:53 AM CDTSevere Thunderstorm WarningLUBDickens43 min
Jun 7, 2:28 AM CDTSevere Thunderstorm WarningLUBKing62 min
Jun 7, 3:01 AM CDTSevere Thunderstorm WarningLUBStonewall44 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 00:00Z, 2.7 hours before the alert went out and 100 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Amarillo Airport, TX at 00:00Z on 2021-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1369 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Amarillo Airport, TX at 00:00Z on 2021-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 37 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1369 J/kg
Mixed-layer CIN
-59 J/kg
Mixed-layer LCL
2265 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
37 m²/s²
0-3 km storm-relative helicity
230 m²/s²
Significant tornado parameter
0.0
Supercell composite
11.2

Open this sounding in Storm Lab

The text

As transmitted.

740 
WWUS20 KWNS 070240
SEL0  
SPC WW 070240
TXZ000-070800-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 240
NWS Storm Prediction Center Norman OK
940 PM CDT Sun Jun 6 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  The southern Texas Panhandle and South Plains

* Effective this Sunday night and Monday morning from 940 PM
  until 300 AM CDT.

* Primary threats include...
  Scattered damaging wind gusts to 70 mph possible
  Isolated large hail events to 1.5 inches in diameter possible

SUMMARY...Thunderstorms are developing rapidly with the collision of
outflow from New Mexico and the retreating dryline, and storms are
expected to persist as line segments or clusters into the overnight
hours while spreading east-southeastward.  Damaging winds and large
hail will be possible with the stronger embedded storms.

The severe thunderstorm watch area is approximately along and 65
statute miles east and west of a line from 35 miles northeast of
Amarillo TX to 60 miles southeast of Lubbock TX. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU0).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
28025.

...Thompson

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 6, 8:49 PM CDTMesoscale DiscussionSPCArmstrong, Briscoe, Carson, Castro, Crosby, Dawson and 14 more116 min
Jun 6, 11:47 PM CDTMesoscale DiscussionSPCBriscoe, Cottle, Crosby, Dickens, Floyd, Garza and 8 more88 min
Jun 7, 1:37 AM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Childress, Coleman, Cottle and 20 more83 min
Jun 7, 2:48 AM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Callahan, Clay, Cooke, Denton and 17 more7 hr
Jun 7, 4:12 AM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Foard, Hardeman, Haskell and 12 more93 min
Jun 7, 7:19 AM CDTMesoscale DiscussionSPCCallahan, Comanche, Eastland, Erath, Hood, Johnson and 3 more116 min
Jun 7, 9:36 AM CDTMesoscale DiscussionSPCAnderson, Angelina, Bosque, Cherokee, Ellis, Falls and 16 more2 hr
Jun 7, 12:32 PM CDTSevere Thunderstorm WatchSPCAngelina, Bowie, Camp, Cass, Cherokee, Franklin and 24 more6 hr
Jun 7, 3:08 PM CDTMesoscale DiscussionSPCSabine, San Augustine, Shelby2 hr

Nearby

Severe Thunderstorm Watches in Texas, 2021Every severe thunderstorm watch in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.